Laboratories, and particularly hospital laboratories, conduct tests on various liquid materials, such as disease causing organisms, isolated from the system of an infected patient. Such testing typically requires that many substantially similar tests be performed on small samples of the clinical isolates. Similarly, such testing may require the exposure of a large number of isolates taken from different patients to a single particular test medium in order to determine which of the samples contains a particular disease causing organism or which of the samples is susceptible to a single particular antimicrobic.
Such testing is exact and time consuming work. Consequently, it is particularly desirable if a large number of specimens can be simultaneously applied to a single test medium or antimicrobic in order to minimize the man hours of skilled laboratory technicians necessary to conduct all tests with respect to a fixed group of clinical isolates.
Various structures have been designed to facilitate this transfer and exposure of a plurality of isolates to the test medium. One such structure is illustrated in Canadian Pat. No. 990,101 issued to Berend C. deKat on June 1, 1976. The structure of that patent is referred to in the trade as a replicator innoculating device. Such devices typically include a base structure and a support pillar to which a transport mechanism is rotatably coupled. The transport mechanism includes a plurality of downwardly extending pins.
The base plate carries a multiple well container, at one end thereof, and a receiving tray, at the opposite end. The multiple well container is keyed to the base plate to make it orientable whereby each of the pins carried by the transport mechanism can, when the mechanism is in a position directly above the well container, enter one of the wells. The mechanism can, thereafter, be moved to a second position wherein the pins are made to engage the surface of a test medium or antimicrobic reagent. An amount of the broth containing the disease causing organism from the clinical isolate can, thereby, be deposited on the surface of the medium or reagent.
The transport mechanism is typically structured so that the pins extend generally vertically regardless of the positioning of the transport mechanism with respect to the multiple well container and receiving tray. The small amounts of the broths adhering to lower portions of the pins as a result of the pins being partially immersed in the liquids disposed in each of the wells will be facilitated in running off of the surfaces of the pins and onto the medium or reagent.
Generally, however, the amount of the broth which adheres to each pin is sufficiently small and surface tension is sufficiently great so that the broth will not drain onto the medium unless the pins are made to engage the surface thereof. It is, however, desirable that the surface of the medium be maintained uniformly flat. This is so since accurate determinations cannot be made unless contamination of one of the broths by another is precluded. Additionally, best results are achieved when the broth is applied to the medium in a fine film rather than puddled in a small indentation which can be formed in the surface of the medium if too much pressure is applied thereto by the transport mechanism and the pins carried thereby.
It is to this shortcoming in the prior art that the invention of the present application is directed. The IMPROVED REPLICATION of this application provides structure which minimizes the likelihood of indentations being formed in the surfaces of the medium and facilitates the application of the broths in the desired film form.